JPH03257321A - Relative position detecting apparatus of underground excavator - Google Patents

Abstract

PURPOSE:To detect at low costs the relative position of two excavators subjected to underground joining by detecting peaks of detecting signals of three or more magnetic field detectors, and obtaining time differences between the peaks. CONSTITUTION:A magnetic field generator 41 of one underground excavator 10 generates an alternating current magnetic field because of the power supply from an alternating current motor 16. The magnetic field is detected by magnetic field detecting coils 26a-26c mounted at end parts within boring machines 24a-24c of the other excavator 20, and amplified by amplifiers 30a-30c. Further, a peak of the output signals is detected and sent to a peak generating time difference measuring circuit 34, where the time difference of the peak detecting signals is obtained and sent to a position operational circuit 36. In the circuit 36, the positional displacement of the center of the excavator 20 to the center of the excavator 10 is operated from the excavating amount of the machines 24 and the output of the circuit 34. The displacement is displayed at 38. Moreover, the circuit 36 obtains the relative distance between the excavators 10 and 20 from the excavating amount of the machines 24, and operates the inclining angle and inclining direction from the difference of the excavating amount of the machines 24.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is suitable for detecting a positional shift between two underground excavators that are started facing each other and are joined underground. This invention relates to a relative position detection device for an underground excavator.

[Conventional technology]

When constructing a tunnel under the sea, it is not possible to install many vertical shafts for launching underground excavators.

However, digging over long distances with one underground excavator not only makes it difficult to discharge the excavated soil, but also involves many dangers. Therefore, when constructing an undersea tunnel, in order to shorten the excavation distance of an underground excavator, two
Underground excavators are set up facing each other and started, and the tunnels excavated by the underground excavators are connected underground.

However, at the junction, the centers of both underground excavators are on the left and right,
If there is a vertical shift, the connected tunnel will become discontinuous, so it is necessary to find the relative positions of both underground excavators and correct the positional shift. Conventionally, when correcting the positional deviation between two underground excavators, both of them are corrected by detecting the positional deviation of each underground excavator with respect to the tunnel planning line and the position from a reference position such as the starting point. The relative positional deviation between underground excavators was determined and corrections were made based on this positional deviation.

Conventionally, the following methods have been used to locate underground excavators underground.

■ Determine the position of the underground excavator from the reference point and the deviation from the planned line by underground surveying using transit, etc.

■ An optical transmitter that generates coherent light such as a laser beam is installed in the starting shaft of the underground excavator, and this device illuminates the tunnel planning line and illuminates the light spot on the target attached to the underground excavator. Read and determine the position, deviation, and declination of the underground excavator from the starting shaft.

■ Combining an azimuth gyro, pressure-type subsidence gauge, inclinometer, and odometer based on the segment length assembled in the tunnel, the relative position from the reference position is determined.

However, each of the conventional methods for determining the position of the underground excavator described above has the following drawbacks, making it difficult to accurately perform underground joints.

Method (2) is impractical because it requires many measurement points when excavating a tunnel in a curved manner, and it is not possible to measure in real time. Furthermore, in method (2), if the tunnel planning line is bent, the laser beam from the starting shaft may not be able to irradiate the target, and the optical transmitter must be moved to an appropriate position. Moreover, since the laser beam cannot be directly irradiated over the entire length of the planned line, each time the optical transmitter is moved, the mutual positional relationship between the target, the optical surveying device, and the tunnel planned line is actually measured, and based on the measurement results, After determining the planned route through calculations, the location, deviation, and yaw angle of the underground excavator must be calculated. For this reason, there is a problem in that the relocation, measurement, and calculation of the optical transmitter requires manpower, which reduces the efficiency of excavation work.

Furthermore, method (■) causes cumulative errors and is not suitable for long-distance excavation, and is also not suitable for excavating curves with a small radius of curvature or excavating tunnels with continuous curves. It is also unsuitable.

In addition, when measuring the relative positions of two underground excavators, as in the case of underground joints, the error further increases.

On the other hand, small underground excavation machines (
For example, as a method for detecting the position of a mini-mall, there is a method that combines an electromagnetic field transmitter/receiver and an inclinometer. This system detects the magnetic field generated by a transmitting loop coil installed on the earth's surface using a receiving coil installed inside the excavation machine, determines the horizontal deviation of the excavation machine from the center of the loop coil, and uses an inclinometer. The position of the excavating machine in the depth direction is obtained from the value and the digging distance of the excavating machine.

However, even in this case, since the positions of the two underground excavation machines to be joined underground are determined, if a detection error occurs, the joining cannot be performed accurately.

Therefore, receiving coils for horizontal position detection and vertical position detection are provided on one of the two excavating machines to be joined, and this receiving coil is made to protrude from the excavating machine by means of an industrial unit, and the other excavating machine serves as the reference position. It is conceivable to detect the relative positional deviation between the two excavating machines by placing the receiving coil close to the transmitting coil attached to the cutter face of the excavating machine and detecting the deviation of the receiving coil with respect to the center of the transmitting coil.

[Problems to be Solved by the Invention] However, the above method of determining the relative position of two excavating machines by providing a transmitting coil on one side and a receiving coil on the other side of the two excavating machines to be joined does not solve the problem of vertical position deviation. This requires a receiving section for detecting the displacement in the horizontal direction and a receiving section for detecting the positional shift in the horizontal direction, making the device complicated and expensive. Moreover, each receiving section is constructed by a pair of receiving coils arranged orthogonally,
Since it is necessary to detect the value of the induced electromotive force generated in these coils to determine the strength of the magnetic field caused by the transmitting coil, the mounting of the receiving coil may result in detection errors depending on the accuracy, and the posture of the receiving coil must be determined strictly. There is a need.

In addition, since it is necessary to read the value of the detection signal, the magnetic field generated by the transmitting coil can only generate a low-frequency magnetic field with little attenuation in the soil, making it difficult to increase the receiving sensitivity of the receiving coil. .

The present invention has been made to eliminate such drawbacks, and it is possible to determine the relative position of two underground excavators to be joined underground without determining the value of the detection signal output by the magnetic field detector. The purpose of the present invention is to provide a relative position detection device for an underground excavator.

[Means to solve the problem]

In order to achieve the above object, a position detection device according to the present invention is provided with a magnetic field generator provided in the front part of one of the underground excavators to be connected underground, and a magnetic field generator provided in the one of the underground excavators, A rotating device that rotates a magnetic field generator in a plane perpendicular to the axis of the underground excavator, and a tag installed non-linearly in the other underground excavator to be connected underground, which rotates the magnetic field generated by the magnetic field generator. three or more magnetic field detectors to detect; a propulsion device provided on the other underground excavator to bring each magnetic field detector close to the one underground excavator; a peak detection circuit for detecting a peak; a peak occurrence time difference measuring circuit for determining the peak interval of the output signal of each of the magnetic field detectors based on the output signal of the peak detection circuit; and a peak occurrence time difference measuring circuit based on the output of the peak occurrence time difference measuring circuit. The present invention is characterized in that it includes a position calculation circuit that calculates relative positions between the underground excavators in each region.

[Effect]

In the present invention configured as described above, when the magnetic field generator is rotated by the rotating device, the detection signal of each magnetic field detector changes periodically. Therefore, the peak detection circuit detects the peak of the detection signal of each magnetic field detector, and the time interval at which the peak of the detection signal between the magnetic field detectors appears is determined by the peak occurrence time difference measuring circuit, and is input manually to the position calculation circuit. The position calculation circuit calculates the angle between each magnetic field detector as seen from the center of the underground excavator equipped with the magnetic field generator from the time interval determined by the peak generation time difference measurement circuit, and calculates the angle between each magnetic field detector as seen from the center of the underground excavator equipped with the magnetic field generator, and calculates the angle between each magnetic field detector to be connected underground. Find the relative position between.

Therefore, in the present invention, it is only necessary to be able to detect that the magnetic field generator has passed in front of or near the magnetic field detector, and when the magnetic field detector is configured with a coil, changes in the magnetic field can be easily detected with a single coil. In addition, the device is inexpensive, and since there is no need to determine the value of the detection signal itself, there is no need to strictly determine the attitude of the coil, and errors are less likely to occur. In addition, since it is only necessary to detect changes in the magnetic field, the effect of attenuation in the soil is small, and the frequency of the magnetic field generated by the magnetic field generator can be increased, increasing the detection sensitivity of the magnetic field detector. It is possible to detect the relative positions of both underground excavators even if they are far from the magnetic field generator.

[Embodiments] Preferred embodiments of the positional deviation detection device of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a configuration diagram of a relative position detection device for an underground excavator according to an embodiment of the present invention.

In FIG. 1, an underground excavator 10.20 has a cutter drum 12.22 with a cutter not shown. This cutter drum ■2.22 is rotatable and
It can be stopped at any rotational position. Further, the underground excavators 10 and 20 have a cutter drum 12.
．． By moving forward while rotating the cutter 22, the earth and sand excavated by the cutter is taken into the cutter drum 12.22 and transported rearward by a screw conveyor or the like. And these underground excavators 10.
The tunnels 20 are excavated from different starting shafts in directions approaching each other along the tunnel planning line, and the excavated tunnels are joined together.

One of the underground excavators 10 has a magnetic field generator 14 attached to the front or inside of the cutter drum 12. This magnetic field generator 14 is connected to an alternating current source 16, is supplied with power from the alternating current source 16, and generates an alternating magnetic field. Further, as shown in FIG. 2, the magnetic field generator 14 consists of a rectangular transmission loop cable, and when the cutter drum 12, which serves as a rotating device for the magnetic field generator 14, rotates, The excavator IO rotates together with the cutter drum 12 as shown by an arrow 18 around the center 01o.

Then, when the cutter drum 12 stops at the reference position, the magnetic field generator 14 causes the long side of the transmission loop cable to become parallel to the Z axis, which is the vertical axis of the underground excavation [10].
The card transmission loop cable is arranged above the center 01° so that the center of the cable is located on the Z axis.

The other underground excavation 1a20 is provided with small-diameter poling devices 24a, 24b, and 24c of a compaction type at the front.

At the tip inside each boring device 24a, 24b, 24C, there are detection coils 26a, 2 which are magnetic field detectors.
6b and 26c are attached (see FIG. 3), so that the magnetic field generated by the magnetic field generator 14 can be detected.

The boring devices 24a, 24b, and 24c are arranged on the circumference of the underground excavator 20 at an interval of 120 degrees with respect to the center 020 on a circumference with a radius r centered at the center 02°, and the boring device 24a is It is located on the vertical axis (Z axis) passing through the center 02° of the medium excavator 20. The boring devices 24a, 24b, and 24C are provided on the rear side of the cutter drum 22, and when the cutter drum 22 stops at the reference position, the boring devices 24a, 24b, and 24C are used to perform underground drilling through a through hole (not shown) formed in the cutter drum 22. It can move forward and backward parallel to the axis (X-axis) of the machine 20, and the detection coils 26a, 26b, 26
c serves as a propulsion device that brings the underground excavator 10 close to the front surface of the underground excavator 10.

Each detection coil 26a, 26b, 26c has a preamplifier 28a, 28b, 28C (preamplifier 28b, 28c), respectively.
8c is not shown) to amplifiers 30a, 30b, 30.
The detection signal is amplified by a preamplifier and an amplifier.

Peak detection circuits 32a, 32b, 32c are connected to the output sides of the amplifiers 30a, 30b, 30c, and detect the peaks of the output signals of the detection coils 26a, 26b, 26c. The peak detection signal is input to the peak occurrence time difference measuring circuit 34. The peak occurrence time difference measuring circuit 34 includes peak detection circuits 32a and 3.
Based on the input times of the peak detection signals from 2b and 32c, the time difference between each peak detection signal is determined and sent to the position calculation circuit 36.

The position calculation circuit 36 includes a polling device W as described later.
24a, 24b, 24c and the output of the peak occurrence time difference measuring circuit 34, the relative distance between the underground excavators 10 and 20 is determined, and the center 01 of the underground excavator 10 is determined.
The amount of positional deviation of the center of the underground excavator 10 by 02° with respect to the angle of 02° is calculated and outputted to the display device 38 for display.

The operation of the embodiment configured as described above is as follows.

The cutter drum 22 of the underground excavator 10 is stopped at the reference position, and the boring devices 24a, 24b, and 24C are advanced toward the underground excavator 10, so that the tip of each boring device reaches the front of the underground excavator 10. let Then, the digging distance of each boring device 24a, 245.24c is manually input to the position calculation circuit 36. Note that the fact that the tip of the boring device has reached the underground excavator 10 can be easily detected by detecting the digging resistance of the boring device 24 or the like.

When the tips of the polling devices 24a, 24b, and 24c reach the front of the underground excavator 10, the cutter drum 12 of the underground excavator IO is rotated at a predetermined rotation period T as shown by the arrow 19 in FIG. .

When the cutter drum 12 rotates, the magnetic field generator 14 provided in the underground excavator 10 rotates together with the cutter drum 12,
Detection coils 26a, 26b provided inside the boring apparatus i 24a, 24b, 24C.

Pass in front of 26c one after another. And each detection coil 2
6a, 26b, and 26c output the induced voltage due to the magnetic field generated by the magnetic field generator 14 as a detection signal.

The detection signals output by the detection coils 26a, 26b, 26c are amplified by preamplifiers 28a, 28b, 28c and amplifiers aoa, aob, 30c, respectively, and sent to peak detection circuits 32a, 32b, 32c. Peak detection circuits 32a, 32b.

32c are the corresponding amplifiers 30a, 30b, 3
The value of the detection signal inputted from 0c is captured at predetermined time intervals, for example, every 10 ms, and is sequentially compared. That is,
The peak detection circuit 32a captures the detection signal of the detection coil 26a amplified by the amplifier 30a at predetermined time intervals, compares the level of the detection signal captured this time with the level of the detection signal captured last time, and detects the peak of the detection signal. .

When each peak detection circuit 32a, 32b, 32c detects the peak of the detection signal outputted by the corresponding detection coil 26a, 26b, 26c, it sends the peak detection signal to the peak occurrence time difference measuring circuit 34. The peak generation time difference measuring circuit 34 includes each peak detection circuit 32a, 32b, 3
When the peak detection signal is input manually from 2c, the difference between the time when the peak detection signal is input from the peak detection circuit 32a and the time input from the peak detection circuit 32b, and the time when the peak detection signal is input from the peak detection circuit 32a is calculated. The distance from the time manually input from the peak detection circuit 32c is determined and input to the position calculation circuit 36.

The position calculation circuit 3G includes boring devices 24a, 24b,
The relative distance between the underground excavator 10 and the underground excavator 20 is determined from the amount of excavation 24c, and each boring device 124
Due to the difference in the amount of excavation of a, 24b, and 24c, underground excavation [2
The angle of inclination and direction of inclination for the underground excavator 10 of 0 are calculated. Further, the position calculation circuit 36 calculates the position of the underground excavator 20 based on the difference between the time when the center of the magnetic field generator 14 passes the Z-axis and the time when the magnetic field generator 14 passes the detection coil 26a. Find the rolling angle for 10.

Furthermore, the position calculation circuit 36 calculates the obtained rolling angle and
Based on the difference in time (time difference) at which the detection signal (output voltage) between each detection coil 26a, 26b, and 26C outputted by the peak generation time difference measuring circuit 34 reaches its peak, the underground excavator 1
0 and the underground excavation @20, that is, the position of the center 02° of the underground excavator 20 with respect to the center 010 of the underground excavator 10.

As shown in FIG. 4, when the center 0 of the underground excavator 10 and the center 02 of the underground excavator 20 coincide, when the magnetic field generator 14 rotates with a period T, Each detection coil 26a, 26b, 26c is 1
Since they are arranged at 20 degree intervals, the detection coils 26a, 2
The peak interval of the detection signal between the detection coils 6b is T/3 as shown in FIG. 5, and the peak interval of the detection signal between the detection coils 26a and 26C is 2T/3. Therefore, when the peak interval of the detection signal determined by the peak occurrence time difference measuring circuit 34 is as shown in FIG. 5, the position calculation circuit 3G determines that there is no positional deviation between the underground excavators 10 and 20. Display bag W
Displayed on page 38.

On the other hand, as shown in FIG. 6, when there is a positional deviation between the underground excavator 10 and the underground excavator 20, the peak interval of the detection signal between the detection coils 26a and 26b becomes Tab. The peak interval between the detection coils 26a and 260 is T
me (see Figure 7).

Now, when the center O8° of the underground excavator 10 is set as the origin of the Y-Z coordinates, the boring devices 24a to 24c installed in the underground excavator 20 are positioned as shown in FIG. 8 with respect to the origin 01G. Suppose we did. And the boring devices 24a to 24
Since c is arranged at intervals of 120 degrees with respect to the center 020 of the underground excavator 20, it is located at the apex of an equilateral triangle whose -side length is l.

Therefore, the position calculation circuit 36 calculates the angle θah between the polling devices 24a, 24b (detection coils 26a, 26b) as seen from the origin 010, based on the rotation period T of the magnetic field generator 14 and the peak interval T ab + T ac. The angle θac between the devices 24a and 24c (detection coils 26a and 26c) is determined as follows.

T ac = T x : −−−−−−−−−−
−−−−−−(1) 60 T,,=Tx−”b bow −−−−−−−−−−1−−−
(2) 60 θ,,=360°x” Ic −,,−,,,,
, -, , -, , , , (3) θ, , = 360°
The coordinates of 4a, 24b, 24C are (ay, az), (by
, b2), (cy, cz), and the angle formed by the line segment connecting the origin 010 and the boring device 24c with the Y axis is φ, then the following equations (5) to (11) can be obtained from the geometrical relationships. It will be done.

jan (ψ+θ3.) -Yoshihi -------(5
”) a.

jan (ψ) −Cz −−−−・−−−
−−−−〜−1(7)Cy b 2 = cz
・(8) cy-b y=1.
−−−−−−−−−−− (9) a y= (b y
+ c y ) / 2 −−−−−−−−−
(10) E is known and θac+θ8. is the formula (3
), (4), the unknowns are ψ, a
There are seven types: 2, az, by-, bt, Cy, and C2.

Therefore, each unknown quantity can be solved using equations (5) to (11).

From equations (5), (10), and (11), jan (ψ+θ3c) = -Li- ay jan (ψ+θIc) = (tan (ψ+
θ3e−θ3. ) tanψ= c, -- C.

2 z+by From equations (12) and (9), (12) Transform equation (15), substitute equation (16) into (14), and rearrange it to jan
(ψ+θIIc) = (tanψ ・jan (
ψ+θ3c−θ3. )tanψ))
(17) Since only ψ is an unknown quantity in Equation (17), the roundness can be determined by a successive approximation method using a computer.

Furthermore, using equations (16) and (6), , b2, equation (
9), using (8), C7, C2, equations (10), (11
) can be used to sequentially find ay and a2.

Therefore, the coordinates P (P,
, P2) is P y= a , −−−−−−−−−
----(18) P, = a, -C1l/-r') -
−−−−−(19) can be obtained, underground excavator 1
A relative position of 0.20 is obtained.

In this way, in the embodiment, the detection coils 26a, 2
The relative position of the underground excavator 10.20 can be determined simply by detecting the peaks of the output signals 6b and 26c and knowing the time at which the peaks occur. Therefore, in order to detect the strength of the magnetic field generated by the magnetic field generator 14, it is not necessary to arrange the coils orthogonally, and the magnetic field detector can be configured with a single coil, making the device inexpensive and Since there is no need to determine the absolute value of the detection signal, there is no need to strictly determine the attitude of the coil. Moreover, the center ○. There is no need to separately provide a detector for detecting positional deviation in the Z-axis direction and a detector for detecting positional deviation in the Y-axis direction.
The device is simple and inexpensive.

In addition, since it is only necessary to detect changes in the magnetic field, and the effect of attenuation in the soil is small, the frequency of the magnetic field generated by the magnetic field generator can be increased, and the detection sensitivity of the magnetic field detector can be increased. It is possible to detect the relative positions of both underground excavators even if they are far from the magnetic field generator.

In the above embodiment, a case has been described in which the magnetic field generator 14 is located in the radial direction from the center of the underground excavator 10. A plurality of them may be provided. In the embodiment described above, the case where the magnetic field generator 14 is a transmission loop cable has been described, but the magnetic field generator 14 may be a permanent magnet or the like.

Furthermore, in the above embodiment, a case was explained in which there were three detection coils, which are magnetic field detectors, but there were four detection coils.
There may be more than one. Further, as long as three or more detection coils are arranged so as not to be lined up in a straight line, it is not necessary to arrange them on the circumference centered on the center of the underground excavator 20. Furthermore, in the embodiment, the detection coil 26a
, 26b, and 26c are arranged at equal angular intervals of 120 degrees with respect to the center 02o, but they do not need to be arranged at equal angular intervals. Further, the magnetic field detector is not limited to a coil, and may be any device capable of detecting a magnetic field such as a magnetoresistive element. Furthermore, in the embodiment, the detection coil 26
A case has been described in which a consolidation digging type poling device is used as a propulsion device to advance a, 26b, and 26c.
The propulsion device is not limited to this.

〔Effect of the invention〕

As explained above, according to the present invention, two underground excavators are connected underground by detecting the peaks of detection signals of three or more magnetic field detectors and determining the time between the peaks. Since it is possible to determine the relative position between the two and there is no need to detect the value of the detection signal itself, an inexpensive device can be obtained.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a relative position detection device for an underground excavator according to an embodiment of the present invention, FIG. 2 is a front view of a magnetic field generator installed in the underground excavator while being connected underground, and FIG. The figure is a front view showing the arrangement of the magnetic field detector installed on the other underground excavator to be joined underground, and Figure 4 is an explanatory diagram of the positional deviation detection method when the centers of each underground excavator are aligned. , Fig. 5 is a diagram showing the peak interval of the detection signal when the centers of the excavators in each region coincide, Fig. 6 is a conceptual diagram showing the state in which the excavators in each region are misaligned, and Fig. 7 The figure shows the peak interval of the detection signal when the center of each underground excavator is shifted, and FIG. 8 is an explanatory diagram of how to determine the relative position of two underground excavators. 10.20---1 underground excavator, 12~・1 rotation device (cutter drum), 14---1 magnetic field generator, 2
4a-24 c--propulsion device (poling device j),
26a to 26c----1 magnetic field detector (detection coil), 32a to 32c---Peak detection circuit, 34-
1---Beak generation time difference measuring circuit, 36 ・---
-One-position calculation circuit.

Claims (1)

[Claims] (1) A magnetic field generator installed at the front of one of the underground excavators to be connected underground; three or more magnetic field detectors arranged non-linearly on the other underground excavator to be connected underground and detecting the magnetic field generated by the magnetic field generator; A propulsion device that is installed in the underground excavator and brings each magnetic field detector close to the one underground excavator, a peak detection circuit that detects the peak of the detection signal of each of the magnetic field detectors, and an output of this peak detection circuit. a peak occurrence time difference measuring circuit for determining the peak intervals of the output signals of the respective magnetic field detectors based on the signals; and a position calculation for determining the relative positions between the respective underground excavators based on the output of the peak occurrence time difference measuring circuit. A relative position detection device for an underground excavator, comprising a circuit.